Container resistant to deformation due to variations in the volume of the contents thereof



9 CONTAINER RESISTANT TO DEF'ORMATION DUE TO VARIATIONS THE VOLUME OF THE CONTENTS THEREOF Filed Nov. 12, 1964 July 30, 1968 ET 'AL 3 39I4,840

FIG. I.

FIG. 2.

INVENTORS GIORGIO PECCI VITTQRIO GHISOLFI W KW ATTORNEY United States Patent 2 Claims (Cl. 220-68) ABSTRACT OF THE DISCLOSURE Closing device for flexible fluid containers comprising a rigid, air permeable flat cap and a single, flexible, impermeable sheet sealed to the outer edges of said cap. The deformation of the container due to internal and external pressures thereon is prevented by provision of the flexible impermeable sheet in the closing device, which sheet flexes in response to such pressure changes.

This invention relates to a container closing device and to the containers, more particularly to thin-walled containers for fluids, incorporating said closing device for rendering the body of the container resistant to deformation in response to changes in the volume of the fluid packaged therein.

Even when sealed perfectly immediately after filling, thin-walled containers for fluid (liquids or gases) made of flexible or semi-rigid material, and generally made of plastic, rubber or the like, are subject to deformation due to changes in the volume of the packaged fluid in response to variations in the environmental conditions to which the containers are exposed, particularly during storage, including variations in temperature, pressure, humidity and so on, and depending, also, on the fluid packaged in the container. As a result, the containers do not maintain their initial dimensions and shape.

The resistance of the containers to changes in dimensions and shape due to variations in the volume of the contents thereof could be increased by increasing the thickness of the container wall or walls. However, this would materially increase the cost of the containers and is not economically feasible.

It has been proposed to provide the deformable thinwalled containers with an expansion chamber which communicates with the ambient air but which is disposed within the fluid-receiving body portion of the container defined by the thin wall or walls and occupies a portion of the total volume of the container. This disposition implies a disadvantageous reduction of said container volume.

A first object of this inventioin is a new closing device for containers.

Another object of the invention is to provide new containers, particularly containers for liquids and gases, which have the conventional thin wall or walls but which comprise a new and novel closing system which inhibits alteration of the initial dimensions and shape of the container due to variations in the volume of the contents thereof without reducing the initial capacity of the fluidreceiving body portion of the container and without being immersed in the fluid content.

The novel closure device of the invention consists of two elements, one of which is a rigid, air-pern1eable cap or closure element, and the other of which is a flexible sheet element which is impervious to air and to the contents of the container. The flexible impervious sheet of the closure device is normally disposed outside the fluidreceiving body portion of the container, under the rigid 3,394,840 Patented July 30, 1968 closure element, and extends transversally of the longitudinal axis of the thin-walled body portion. The flexible impervious sheet thus does not reduce the normal, initial capacity of the container.

The rigid closure element, cap or cover may be, and in general preferably is, made of metal and rendered airpervious by being provided with one or with a plurality of holes which permit air to pass into, or out of, the space between the rigid element and the flexible element. Alternatively, the rigid closure element may be made of a porous or gas-pervious material.

The flexible element consists of a single sheet or lamina of any material which is impervious to air and to the fluid packaged in the container, and capable of flexing readily under the pressure of air or of the fluid packaged in the container, to permit of the contraction or expansion of the fluid in response to environmental variations, without alteration in the initial dimensions and shape of the container. The flexible impervious sheet, which forms a hermetic seal for the contents of the container, may normally be linear or it may be corrugated.

The flexible sheet can be sealed to the outer edges of the rigid closure element and the sealed elements, which together constitute the novel closure device for the con tainer, can be aflixed to the container in a single operation.

As is known, a seat or seats are provided at the top of the longitudinal wall or walls defining the body of the container, for receiving the cap or cover, and, after the container is filled by an automatic machine, the cap is placed on the seat or seats and sealed thereto by the machine.

According to one embodiment of the present invention, the flexible impervious sheet element and the rigid closure element are co-extensive and disposed transversely of the longitudinal axis of the thin-walled body portion of the container. This is very advantageous since after the containers are filled by means of the automatic machine, the flexible element and then the rigid element can be placed on the seat or seats provided at the top of the container wall or walls and simultaneously sealed to each other and to the container by a single automatic pinching operation. Because of the special disposition of the flexible member transversely of the longitudinal axis of the thinwalled body portion of the container, it is unnecessary to seal the flexible element to the rigid element in a separate operation before fixing the closing system on the container. The invention thus has the important advantage that conventional filling and pinching machines can be used without change or modification, and without need for any additional operation, due to the use of the flexible impervious sheet for compensating for expansion or contraction of the volume of the fluid packaged in the container.

When the volume of the fluid is reduced, the flexible impervious sheet of the closure device will dilate freely inside the container, thereby inhibiting deformation of the container.

The flexible impervious sheet or lamina may have any appropriate design. By selecting a sheet of suitable design, it is possible, owing to the leaking hole or holes in the rigid closure element (or the natural permeability thereof if the rigid element or cap is made of porous or gaspervious material) to compensate for any increase or decrease in the volume of the fluid packaged in the container without varying the capacity of the container, and thus to neutralize the deforming effect on the container of the increase or decrease in the volume of the fluid contained therein.

The closing device of the invention is particularly useful for mineral and lubricating oil containers.

Thus, the present invention provides in combination, a container for fluids and a closure device therefor, said container comprising a thin-walled deformable body portion capable of being deformed by internal-external pressure differentials of less than one atmosphere, said body portion having an internal seating ledge adjacent and paralleling the top edge of said body portion for receiving said closure device, said closure device comprising a substantially horizontal rigid air-permeable closure element and a substantially horizontal flexible sheet which is impermeable to air and to the intended contents of said container disposed beneath said element, said closure element having a first flange portion extending axially upwardly from its periphery and a second flange portion extending radially outwardly from the top edge of said first flange portion for cooperating with said seating ledge for securing said device to said container, and means securing said sheet to the lower face of said second flange portion in sealing relationship therewith and free from the lower surface of said horizontal closure element.

In the accompanying drawing illustrating the invention:

FIGURE 1 is a longitudinal sectional view of a closing device embodying the present invention;

FIGURE 2 is a longitudinal sectional view of the top of a flexible container upon which the closing device of FIGURE 1 may be employed;

FIGURE 3 is a longitudinal sectional view showing the closing device affixed to the container;

FIGURE 4a is a longitudinal sectional view of a flexible lamina member suitable for use in the closing device of FIGURE 1;

FIGURE 4b is a longitudinal sectional view of another flexible lamina member suitable for use in the closing device of FIGURE 1;

FIGURE 4c is a longitudinal sectional view of yet another flexible lamina member suitable for use in the closing device of FIGURE 1', and

FIGURE 4d is a partial longitudinal sectional view showing the configuration of the rigid member and the flexible member of a closure device embodying the present invention before formation of the closure device by the pinching action of an automatic packaging machine.

Referring now to the drawings in detail, and with particular reference to FIGURE 1, a closing system or closure device C is illustrated consisting of rigid closure element, cap or cover 1, provided with at least one hole H in its center, and of an impermeable flexible elastic sheet 2 coupled with rigid closure element 1 and sealed to the outer edges 11 and 12 of rigid closure element 1, the flexible, elastic sheet 2 being shown in normal, unexpanded condition.

In FIGURE 2 is shown the top edge of a container 3, prior to fixing closing system C (FIGURE 1) thereto, including the seats or seating ledge S adapted to receive the closure device C.

FIGURE 3 shows the closing system or closure device C aflixed to the container, as by a pinching machine, and illustrates the function of the flexible elastic lamina or sheet 2 which is shown (in dotted line) in expanded condition.

FIGURE 4a shows a flexible elastic sheet 2 for use in the closing system C which is linear in the normal or unflexed condition.

FIGURE 4b shows a flexible, elastic sheet 2 for use in the closing system C which is convex in the normal or unflexed condition.

FIGURE 4c shows a flexible elastic sheet 2 for use in the closing system C which is normally corrugated.

FIGURE 4d shows a flexible elastic corrugated sheet 2 having an expansion 2' which penetrates into the corresponding expansion 1' of the rigid closure element 1. This figure illustrates the advantage of forming a closing system constituted by the transversely disposed flexible sheet element and the rigid closure element during the assembly of the container as a whole on an automatic machine and then simply sealing an pinching the two elements of the closing system to the body portion of the container.

The flexible elastic lamina 2 can be used in combination with any type of air-pervious cap, cover, plug or the like to provide a closing system as contemplated by this invention.

The container proper is usually made of a plastic material such as a polyolefin, laminates, rubber and the like, and may have side and bottom walls of any suitable thickness, usually a thickness of about 0.5 mm.

The impervious flexible lamina or sheet 2 may also be made of a plastic material such as a polyolefin but may be a lamina or sheet of any material which flexes or dilates without rupture under pressure of air passing through the pervious rigid element into the space between the two elements, or under pressure resulting from expansion of the fluid packaged in the container. The thickness of the flexible lamina 2 may vary but is usually of the order of 0.05 to 0.1 mm.

Since it will be obvious that some changes can be made in practicing the invention without departing from its spirit, it is intended to include in the scope of the appended claims all such modifications and variations as may be obvious to those skilled in the art from the description and illustrative drawings provided.

What is claimed is:

1. In combination, a container for fluids and a closure device therefor, said container comprising a thin-walled deformable body portion capable of being deformed by internal-external pressure differentials of less than one atmosphere, said body portion having an internal seating ledge adjacent and paralleling the top edge of said body portion for receiving said closure device, said closure device comprising a substantially horizontal rigid airpermeable closure element and a substantially horizontal flexible sheet which is impermeable to air and to the intended contents of said container disposed beneath said element, said closure element having a first flange portion extending axially upwardly from its periphery and a second flange portion extending radially outwardly from the top edge of said first flange portion for cooperating with said seating ledge for securing said device to said container, and means securing said sheet to the lower face of said second flange portion in sealing relationship therewith and free from the lower surface of said horizontal closure element.

2. The combination of claim 1 wherein said sheet is entirely above the lowermost portion of the seating ledge of said body portion when in the normal, unflexed condition whereby to provide for prevention of deformation of said body portion upon changes in pressure to which it may be subjected without reducing the capacity thereof.

References Cited UNITED STATES PATENTS 324,148 8/1885 Noessel 22044 2,190,826 2/ 1940 Deeley 22044 2,347,976 5/1944 Trapp et al. 22068 2,732,092 1/1956 Lawrence 215-56 2,751,073 6/1956 Sheeran 22085 3,094,239 6/1963 Baker 22066 X 3,149,743 9/1964 'Scholtz 22068 X FOREIGN PATENTS 1,014,627 6/ 1952 France. 1,295,469 5/ 1962 France.

THERON E. CONDON, Primary Examiner.

JAMES R. GARRETT, Assistant Examiner. 

